Avoid duplicate process copy through cron

Scenario:

You are executing a background job for every x minuts periodically.The job execution time takes approximately y mins.Sometimes y > x. So, you are endup with multiple duplicate active process running at back.

Effets:

If duplicate process runs at back, it creates multiple side effect. The one is you would surprise to see the duplicate record in your table.

So, We can write a shell script which should check whether any active same process running or not? If not, spawn one.

Trick:

This trick might help to you.

#!/bin/bash

status=`ps -efww | grep -v grep |grep -w "python manager.py send_email" | awk -vpid=$$ '$2 != pid { print $2 }'`
echo $status
if [ ! -z "$status" ]; then
    echo "Process already running"
else
    cd /home/edge/projects/venv
    source bin/activate

    cd /home/edge/projects/taleo
    python manager.py send_email

    echo "[`date`] New Process Spawned"
fi

my process python manager.py send_email will be grepped before it gets spawned.

your suggestions are welcome 🙂